Selasa, 08 Juni 2010

menghitung luas bangun datar dengan java

interface BangunDatar
{
public double luas();
public double keliling();
}

class segitiga implements BangunDatar
{
double alas;
double tinggi;
public segitiga()
{
alas = 0;
tinggi = 0;
}
public segitiga(double a, double t)
{
alas = a;
tinggi = t;
}
public double GetAlas()
{
return alas;
}
public double GetTinggi()
{
return tinggi;
}
public void SetAlas(double a)
{
alas = a;
}
public void SetTinggi(double t)
{
tinggi = t;
}
public double luas()
{
return GetAlas()*GetTinggi()/2;
}
public double keliling()
{
return 3*GetAlas();
}
}
class PersegiPanjang implements BangunDatar
{
double panjang;
double lebar;

public PersegiPanjang()
{
panjang = 0;
lebar = 0;
}
public PersegiPanjang(double p, double l)
{
panjang = p;
lebar = l;
}
public double GetPanjang()
{
return panjang;
}
public double GetLebar()
{
return lebar;
}
public void SetPanjang(double p)
{
panjang = p;
}
public void SetLebar(double l)
{
lebar = l;
}
public double luas()
{
return GetPanjang()*GetLebar();
}
public double keliling()
{
return 2*(GetPanjang()+GetLebar());
}
}

public class Geometri2D {

public static void main(String[] args)
{
BangunDatar BD;
segitiga bgn1 = new segitiga(6,3);
PersegiPanjang bgn2 = new PersegiPanjang(10,10);

BD = bgn1;
System.out.println(bgn1.luas());
System.out.println(bgn1.keliling()+"\n");

BD = bgn2;
System.out.println(bgn2.luas());
System.out.println(bgn2.keliling());
}

}